The call comes amid rising tensions between Australia and the US over the Iraq wheat scandal involving Australian monopoly exporter, AWB.
US Senator, Norm Coleman, heading the Congressional inquiry into the oil for-food program has asked Australia's Ambassador to Washington, Dennis Richardson, to explain the Howard government's role in the wheat affair.
It followed claims that Australia’s former ambassador to the United States, Michael Thawley, had intervened in 2004 by asking the US Senate committee to drop an investigation into the alleged kickbacks.
Senator Coleman said he was "deeply troubled" by an apparent attempt to cover up the scandal.
A group of U-S senators has also demanded the suspension of AWB from an export credit scheme and another senior American politician has written to the Australian Ambassador in Washington to raise his concerns.
The concerns have been echoed by American wheat exporters.
“We hope that his (Senator Coleman’s) investigators will pick up where they left off in considering an investigation into AWB, because US Senators don’t take kindly to being misled,” Dawn Forsythe of US Wheat Associates told SBS World News.
Opposition Call
The federal opposition renewed its call for the inquiry into the Iraqi wheat scandal involving AWB, to be widened.
"We now have the American congress breathing down our neck, considering that they have been misled," said Federal Labor Leader Kim Beazley.
"That is a very bad position to be in.”
"(Prime minister) John Howard needs to be able to go to the United States, and the rest of the world, and say all the possibilities of this are being properly examined," he said.
Mr Beazley said the role played by government ministers and departmental heads fell outside of the scope of the current Cole inquiry.
Government response
Deputy Prime Minister Mark Vaile has assured furious American senators that Australia is doing its best to get to the bottom of the Iraqi wheat scandal.
But Mr Vaile urged the Americans to wait for the outcome of the Australian probe, the Cole inquiry, into the AWB affair.
"I can assure our colleagues in America that that inquiry is being conducted fully, transparently and openly," Mr Vaile told ABC radio in Rockhampton.
Cole inquiry
Meanwhile in Sydney a former AWB manager has blown the whistle on the wheat exporter's payment of kickbacks to Saddam Hussein’s regime in Iraq.
Mark Emons has told the AWB inquiry senior executives agreed to the system and knew it could be illegal.
The former manager of the company's Middle East Section said he helped set up the system that funnelled money to Saddam’s regime.
Mr Emons said it was common knowledge Iraq was imposing a fee and the issue was widely discussed within the company and they were unsure of the legality of it.